How to make sure you never pay an ATM fee

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That little fee tacked onto your withdrawal when you use an automatic teller machine outside your bank network is not only annoying — it's a terrible financial move.

Just a few dollars might seem insignificant at the time, but what you may not think about is that ATM fees can make up an obscenely high percentage of the money you're withdrawing.

For instance, if you are taking out $50 and you pay a $2.50 fee to the bank whose machine you are using, plus a $2 fee to your own bank, you just paid an additional 9% to access your own money. You wouldn't take out a mortgage at that rate, so don't pay that rate for your own cash!

My husband used to be a serial out-of-network ATM user. I formulated this list of tips to help him avoid the insidious habit.

1. Fill up at 50%

Just like driving mountain roads with the empty tank light blazing, walking around town with an empty wallet is tempting fate. Set an optimal amount of cash to carry at all times — say, $50 — and when your wallet dips below $25, plan a stop at your bank's ATM to refill.

If you tend to spend cash just because it's in your wallet, be craftier about your emergency reserve. Keep it in your car glove compartment, zipped into an inside pocket of your jacket, or in some other out-of-sight place. And if you don't like stopping at the bank when your backup runs out, keep a backup backup, like a drawer at home with $100 for replenishing.

2. Carry a checkbook

Sure, it's super dorky to have to ask an establishment if they'll take a check. But it's better than paying high rates to access your own money. Stash a checkbook in your bag or the glove compartment.

3. Get cash back instead

This is my favorite move in a cash emergency: I stop in a drugstore or grocery store, make a purchase, pay with my debit card, and ask for cash back, which is usually provided with no fee. I try to pick up something I needed anyway — say, envelopes.

But even if I just buy myself a small treat, like a candy bar, as long as it's under $2, I still come out ahead.